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A material that resembles a tiny shag carpet might just be the next big thing in
joint-replacement technology.

Researchers at Ohio State University have developed a nanotech coating that they say can help
bone and tissue better adhere to artificial joints.

The new material is composed of thousands of titanium wires, each only a fraction of the width
of a human hair, and could coat artificial joints and other materials used in orthopedic
surgeries.

“Our hope is that this surface treatment will become a simple-to-implement modification to
titanium implants to help them form a stronger interface with surrounding bone tissue,” said Derek
Hansford, an OSU biomedical engineer and co-author of a paper on the new titanium nano-carpet.

“A stronger interface means that implants and bones will be better able to share mechanical
loads, and we can better preserve healthy bone and soft tissue around the implant site.”

In early tests, the wires boosted cell growth by nearly 80 percent compared with other surfaces.
That means the coating could help healthy bone form a strong bond with an implant faster, the
researchers said.

The hope is that such material will shorten the healing time after broken bones and
joint-replacement surgeries.

Its price tag might appeal to the health-care industry, as well. The technique used to make the
wires is easy and inexpensive, said Sheikh Akbar, an OSU materials scientist specializing in
nano-structures.

Akbar, co-author of the study, said the cost to create each nano-wire carpet is less than
$100.

“Usually, to do nano-scale work, you have to (actually carve) the structures onto the material
using electron-beam lithography equipment,” Akbar said.

That’s expensive. Instead, “We are exploiting the intrinsic properties of the materials to
create structures on the surface,” he said. “It’s really easy. All you have to do is take a sample
of titanium metal and put it inside (a specialized) furnace for six to eight hours.”

During the process, fine filaments of titanium dioxide rise from what was once a smooth titanium
surface.

Other universities are exploring similar technologies. For instance, the Massachusetts Institute
of Technology is developing nanotech coatings made from layered plastic that might help joint
implants better adhere to surrounding tissues.

“The implant industry has been using surface modifications such as plasma-sprayed particles and
sandblast roughening to enhance tissue attachment for quite a while,” Hansford said.

Hansford and Akbar’s nano-wire work is still in its early phases. The two recently published the
results of their study in the journal
Ceramics International.

Simpler, lower-tech solutions would do more to improve the success rate of joint-replacement
surgeries, said Dr. Sharat Kusuma, an OhioHealth orthopedic surgeon.

“The primary reason for joint-replacement failure is that joints come in about 10 sizes and are
not sized or aligned properly for a patient,” he said. “If (the joint) isn’t put in right, the
surface material doesn’t matter.”